[Role of pulsatile liberation of gonadotropins in the development of amenorrhea]

Abstract

The authors performed serial gonadotropin determinations of 25 patients with secondary amenorrhea. In addition repeatedly 17-beta-estradiol, prolactin, testosterone and progesterone determinations were carried out in every case, too. The cause of amenorrhea was hyperprolactinemia in 3 patients and elevated LH secretion (polycystic ovarian syndrome) in 5 other patients. In half of the remaining 18 cases the serial LH levels exhibited a decrease, as well as the physiological pulsation disappeared. Very low prepubertal estradiol secretion and negative gestagene and clomiphene tests were more likely at these patients. The medicinal treatment (Clostilbegyt, Pergonal, Choriogonin) was unsuccessful in more of half of the cases with restricted pulsatile pattern. According to the authors' the cessation of pulsatile LH activity results in the failure of ovarian function, in very low estradiol secretion and in lasting amenorrhea. The hormonal picture is similar to that observed during the prepubertal period (relatively high FSH level, low and tonic LH secretion). The insusceptibility of the adequate receptors in the hypothalamic-pituitary-ovarian system brings about often the failure of the clomiphene or gonadotropin treatment. Since the lack of endogenous gonadotropin-releasing hormone represents the basis of the disorder, the administration of luteinizing hormone-releasing hormone (LH-RH) in appropriate rhythm would be the solution for the patients.